Power mode selection in embedded systems with performance constraints

Mobile computing platforms must provide ever increasing performances under stringent power consumption constraints. Dynamic Voltage and Frequency Scaling (DVFS) techniques allow to reduce the power consumption by providing just enough power to the chip in order to finish the task before its deadline. DVFS is usually achieved by setting the supply voltage and the clock frequency to predefined values (so-called “power modes”) during given durations that depend on the task to be run and on its deadline. Here, the problem of power management is recast as a linear programming one and the computation of the duration spent in each one of the N power modes is obtained with a Simplex algorithm solution. Results for 3 power modes exemplify the proposed approach.